Field
Apparatuses and methods consistent with example embodiments relate to a motion vector estimation method and a motion vector estimation apparatus, and for example, to a motion vector estimation method and a motion vector estimation apparatus for compressing an image or converting a frame rate.
Description of Related Art
A moving image which is acquired through a photographing apparatus such as a camera, a camcorder, etc. includes various objects, and the objects move in various directions. If it is possible to estimate the motions of the objects, video coding or frame rate up conversion could be performed more effectively.
To estimate the motions of the objects included in the image frame, various related-art methods such as full search, 3-step search, recursive search, hierarchical search, etc. are used, and a method of searching an area which has a smallest Sum of Absolution Difference (SAD) value between a current block and a reference block is frequently used.
However, the related-art method is useful for finding data having a smallest SAD value between a current block and a reference block, but may be ineffective in finding a unique motion of an object. For example, it is difficult to find a unique motion vector of a current block in a repeated pattern portion, a flat background portion, and a portion where similar objects overlap each other, which are included in an image.
In particular, when a frame rate is up-converted, finding a unique motion vector is more favorable to image quality than finding a block having a smallest SAD value. However, the related-art SAD-based motion vector estimation method cannot find a unique motion vector.